[SLVSRFR]

Ive been trying to chase down a lean condition on Bank 2 (code P0174)

Dealer has done fuel pressure test, smoke test, and short test.

Car is completely stock, and I'm getting +28% Long Term Fuel Trim under load. At idle, both banks even out at about 15.6%. As soon as I press on the throttle, bank 2 shoots above 22%.

I'm putting money on the fuel injectors but I have no way to prove this theory.

[550Reasons]

yea injectors since they are known to fail, but check the throttle bodies

[MattPro]

If you have access to readouts I would check what each side MAF is reading. If both banks are reading very differently you could have a MAF issue or a vacuum leak that they are missing.

[SLVSRFR]

Originally Posted by MattPro

If you have access to readouts I would check what each side MAF is reading. If both banks are reading very differently you could have a MAF issue or a vacuum leak that they are missing.

Thanks for the info.

I put my car back to stock to try and chase this down.

Dealer originally said the N63intakes may be causing it. But the issue is still present.

I've swapped MAF's today and the lean code still stays on bank 2.

Its possible the dealer forgot to reset adaptations after replacing an o2 sensor and one of my upper intake ducts. Plus I removed my catless DP's right before taking it in. So I'm going to reset adaptations with ISTA with my N63 intakes installed to reset my baseline. Hopefully that works. If not, the only thing left is the fuel delivery on bank 2 or a possible exhaust leak. Unless I'm forgetting something?

Crazy thing is, the car runs perfect. It's just the CEL after 10-30 miles after a reset.

[NV GUNS]

crazy I get the same code with intakes, catted DPs, JB4, and Cat back M5 CP exhaust. but only after I give it a good run on the highway, then I reset it and I don't see it again. always bank 2. I have a N63TU, had a N63 with only intakes and got a hard bank 2 lean fault. dealer said it was a cold air intake fault but I called bs on that. is it a hard fault or a intermittent one?

[SLVSRFR]

Originally Posted by NV GUNS

crazy I get the same code with intakes, catted DPs, JB4, and Cat back M5 CP exhaust. but only after I give it a good run on the highway, then I reset it and I don't see it again. always bank 2. I have a N63TU, had a N63 with only intakes and got a hard bank 2 lean fault. dealer said it was a cold air intake fault but I called bs on that. is it a hard fault or a intermittent one?

After I cleared my codes, reset adaptations, code didn't come back with stock intakes and my fuel trims are near normal. I run a little bit of E85 so my fuel trims will always be higher than normal.

I'm waiting to put my N63 intakes back on.

But when I did have the fault, it would come on every 10 miles and my fuel trims were out of whack.

[badblack550xi]

Originally Posted by SLVSRFR

After I cleared my codes, reset adaptations, code didn't come back with stock intakes and my fuel trims are near normal. I run a little bit of E85 so my fuel trims will always be higher than normal.

I'm waiting to put my N63 intakes back on.

But when I did have the fault, it would come on every 10 miles and my fuel trims were out of whack.

What was your trim position ?

[SLVSRFR]

Originally Posted by badblack550xi

What was your trim position ?

With the intakes installed at idle:



As soon as I apply the throttle, the short term and long term increase above 20%

[badblack550xi]

Only bank 2 correct ?

[SLVSRFR]

Originally Posted by badblack550xi

Only bank 2 correct ?

Both banks go above 20%. STFT and LTFT but bank 2 is slighly higher. Which probably pushes it above the threshold and throws the lean code.

We discussed the proposed issue on IG, hopefully the replacement part fixes it

[Moe_d2]

Hey it says your inbox is full and it won't let me private message you. But I wanted to as what company is the product from and will it automatically clear my cel or will I have to do it manually Everytime?